[GVN] Factor out common code [NFCI]
[GVN] Factor out common code [NFCI]

We had the same code duplicated for each type of Def.  We also have the entire block duplicated between the local and non-local case, but let's start with local cleanup.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@258740 91177308-0d34-0410-b5e6-96231b3b80d8

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